From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: [RFC PATCH 3/6] spi: bcm53xx: Implement the spi_mem interface Date: Tue, 6 Feb 2018 00:21:17 +0100 Message-ID: <20180205232120.5851-4-boris.brezillon@bootlin.com> References: <20180205232120.5851-1-boris.brezillon@bootlin.com> Cc: Peter Pan , Frieder Schrempf , Vignesh R , Yogesh Gaur , =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= , Kamal Dasu , Sourav Poddar To: David Woodhouse , Brian Norris , Boris Brezillon , Marek Vasut , Richard Weinberger , Cyrille Pitchen , linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Mark Brown , linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Return-path: In-Reply-To: <20180205232120.5851-1-boris.brezillon-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: From: Boris Brezillon The spi_mem interface is meant to replace the spi_flash_read() one. Implement the ->exec_op() method so that we can smoothly get rid of the old interface. Note that the current ->flash_read() implementation looks a bit fragile since it does not take the ->read_opcode passed by the spi-nor layer into account, which means if might not work with all kind of NORs. Anyway, I left the logic unchanged and added a few extra checks to make sure we're receiving something that looks like a NOR read operation. Signed-off-by: Boris Brezillon --- drivers/spi/spi-bcm53xx.c | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-bcm53xx.c b/drivers/spi/spi-bcm53xx.c index 6e409eabe1c9..c681d432e26c 100644 --- a/drivers/spi/spi-bcm53xx.c +++ b/drivers/spi/spi-bcm53xx.c @@ -263,6 +263,40 @@ static int bcm53xxspi_transfer_one(struct spi_master *master, return 0; } +static int bcm53xxspi_exec_mem_op(struct spi_mem *mem, + const struct spi_mem_op *op) +{ + struct bcm53xxspi *b53spi = spi_master_get_devdata(mem->spi->master); + u32 from; + + /* + * FIXME: There's nothing in this driver programming the opcode and + * buswidth to be used when a read is done on the mmio window, but it + * seems to be used to access a SPI NOR device, so restrict access + * access to SPINOR_OP_READ commands. + */ + if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN || + op->addr.nbytes != 3 || op->cmd.opcode != 0x3) + return -ENOTSUPP; + + from = ((u32)op->addr.buf[0] << 16) | ((u32)op->addr.buf[1] << 8) | + op->addr.buf[2]; + + /* Return -ENOTSUPP so that the core can fall back to normal reads. */ + if (from + op->data.nbytes > BCM53XXSPI_FLASH_WINDOW) + return -ENOTSUPP; + + bcm53xxspi_enable_bspi(b53spi); + memcpy_fromio(op->data.buf.in, b53spi->mmio_base + from, + op->data.nbytes); + + return 0; +} + +static const struct spi_controller_mem_ops bcm53xxspi_mem_ops = { + .exec_op = bcm53xxspi_exec_mem_op, +}; + static int bcm53xxspi_flash_read(struct spi_device *spi, struct spi_flash_read_message *msg) { @@ -317,8 +351,10 @@ static int bcm53xxspi_bcma_probe(struct bcma_device *core) master->dev.of_node = dev->of_node; master->transfer_one = bcm53xxspi_transfer_one; - if (b53spi->mmio_base) + if (b53spi->mmio_base) { + master->mem_ops = &bcm53xxspi_mem_ops; master->spi_flash_read = bcm53xxspi_flash_read; + } bcma_set_drvdata(core, b53spi); -- 2.14.1 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html